It was caused by a mix of different scenarios. Rome was constantly attacked by Barbarian tribes; they were over-expanded, which made it really hard for them to keep their entire empire under control; they had a lot of economic problems and relied too much on slave labor; and they spent way too much money on their military, just to name a few factors.
Answer:
The process and material that forms a protective seal that hardens around an organism is explained below in complete details.
Explanation:
Arthropods, invertebrates with exoskeletons, use extremely tough shell material such as cuticle as protection. cuticle layers are formed through secretion from the epidermis, continuously building up over time. therefore, wounds are meant to be absorbed by the exoskeletons and prevent damage to the softer inner tissues. the organism does not heal these wounds but continuously bolsters the protective exoskeletons through secretion.
A dolphin swims in the ocean which is the hydrosphere...